At the beginning you must do nothing you only must brows with this app and not with safari. Safari doesn’t support Adblock plugins.
So in my (this) AdBlock Browser the AdBlock Plugin is active for non-pro users for a limited time. So you can test the main-option for free and don’t must buy a pig in a poke.

After your free-trial time is over you must upgrade to pro version to still use the Adblock again.

If you still see some ads please report me the URL via the info-button. So I can find and fix this bugs.